A high-profile report by the government's troubled families' tsar into the scale and nature of dysfunctional households this summer broke a number of ethical guidelines laid down by ministers to protect vulnerable individuals from being harmed or exploited by researchers, an investigation has claimed.

Using freedom of information requests, Nick Bailey, a lecturer in the University of Glasgow's school of social and political sciences, claims that the head of the Troubled Families Unit, Louise Casey, did not "seek or obtain ethical approval" from families interviewed in a much-heralded report published in July.

Bailey also points out that while the names of the 16 families interviewed had been changed, the details on the number, age and gender of children had not, making it possible to identify them.

Bailey said the issues around confidentiality and ethical permissions were "very much live ones in social sciences". On a blog he writes: "A very basic requirement is that people who are asked to participate in social research should be freely able to decline and should not in any way feel pressurised to take part. But the families interviewed were recruited by local authority-run family intervention projects and, as the report notes, these projects had a power of sanction over them. Can the families really be considered free to decline in this case?"

When the researcher complained to the Department for Communities and Local Government (DCLG) that the report appeared to be a "breach of ethical standards", he was told that officials did not consider this "formal research" and that instead the "report falls more properly within the description 'dipstick/informal information gathering'" – which meant that Casey was free to ignore the government's ethical guidelines on research.

Bailey says this claim calls into question why when the report was published Eric Pickles, the cabinet minister in charge of the £450m scheme to help troubled families, hailed Casey's work as providing "real insights into these families' lives" and as offering a "true understanding of the challenges local authorities face".

Bailey said: "The report was portrayed as solid piece of research driving an evidence-based approach to policy making. Ministers ignored its own caveat in the report which said that 'the information [interviewees] gave us is not representative of the 120,000 families that are deemed as troubled'.

"If the report was not proper 'social research', this would raise a whole new set of questions about why it was given such extensive press and media prominence and why it was considered a reliable basis for policy. How many other 'dipstick' exercises have been given such coverage? Is it government policy to move from 'evidence-based policy' to 'policy by dipstick'?"

In response, a spokesman for the DCLG said: "We have always made clear Louise Casey's report was a snapshot view of the lives of 16 troubled families which helped to highlight the kind of lives they lead and the policy challenges to dealing with them. Permission was sought at every stage from the families, the local services working with them and the relevant local authorities.

"On top of this, all names were anonymised, including to the extent that we did not even refer to the geographical area they came from. Working with local authorities, we are focussed on the task of turning around the lives of 120,000 troubled families by 2015, which we are on track to achieve, not engaging in academic debate."